Key Considerations When Purchasing Walk Through Metal Detectors

The prices of walk through metal detectors on the market now range from several thousand to tens of thousands. Faced with walk through metal detectors of varying prices, people often make blind choices. The following will explain how to choose walk through metal detectors and some precautions when purchasing walk through metal detectors.

1>. Detection capability

When a person passes through a walk through metal detector, can they detect the dangerous metal objects hidden in the body 100%, and can they display the location of the dangerous metal objects in multiple sections with high brightness? The detection capability of walk through metal detectors involves the detection uniformity of sensitivity.

1. Sensitivity: The sensitivity of walk through metal detectors is divided into A, B, and C levels, with the highest level being A, which is generally used in prisons, chip detection and other high-requirement industries, while civil aviation requirements are generally B-level, but the detection uniformity requirements are extremely high.

2. Detection uniformity: This is very important for walk through metal detectors. Generally, the bottom control detection capability of walk through metal detectors is weak. Even if the local sensitivity is improved, it is often difficult to reach the highest level requirements. The general test method is to ensure that all locations have an alarm or no alarm for the same metal test object, and each location is tested 10 times. Only high-level walk through metal detectors can achieve uniform detection in each area.

The principle of walk through metal detectors is that when a metal object passes through the magnetic field generated by the pillars on both sides of the door, it will cause magnetic field induction and alarm. This will inevitably lead to the phenomenon that the sensitivity decreases from the two sides of the door panel to the middle area, that is, the sensitivity on both sides close to the door panel is higher than the middle. Now many manufacturers of security inspection machines also produce walk through metal detectors, and claim that they can detect a metal the size of a paper clip, but in fact many manufacturers can barely detect it only when it is very close to the door panels on both sides, and there is no response in the middle. Under the condition of excluding conveyor belt buckles, small metals can be detected, and under the condition of excluding conveyor belt buckles, keys, mobile phones, and coins, controlled knives and firearms can be detected.

There is a certain correlation between detection uniformity and stability. There should be no missed or false alarms. Poor quality walk through metal detectors may give an alarm when approaching their sensitivity limit, but sometimes they may not.

2>. Stability and self-diagnosis function

It has a self-diagnosis function when it is turned on, which can self-discover the faults of each system and display them on the control panel. It can also automatically alarm and stop working when it detects that the surrounding magnetic field affects the work.

3>. Anti-interference ability

Whether it is not interfered by security inspection equipment such as security X-ray machines or other electromagnetic signals, and whether multiple detection doors can be discharged at a close distance (less than 15CM) without interfering with each other.

4>. Anti-seismicity

The door body cannot make continuous sounds when it shakes. The stability and anti-interference ability of a walk through metal detector directly affect the normal use of the walk through metal detector. Some companies and users do not pay attention to the relevant aspects when purchasing walk through metal detectors or are deliberately avoided by some manufacturers, resulting in the principle of magnetic field induction of the purchased walk through metal detectors. When the walk through metal detector vibrates in the magnetic field or the environmental magnetic field, it is easy to cause false alarms. A quality walk through metal detector should not cause false alarms when no one passes by, even if the magnetic field vibrates (such as strong wind blowing, hitting the door panel to cause shaking), but display the current magnetic field abnormality, when the magnetic field vibrates, someone just passes by. It is also necessary to ensure that the signal returns to normal quickly, and false alarms cannot continue.

5>. Detection effectiveness

Generally, walk through metal detectors have the function of automatically counting the number of people passing through and the number of alarms. If the number of people displayed does not match the actual number of people passing through, it may cause missed reports, which means that there are loopholes in security inspection. Good walk through metal detectors should be able to detect a hundred times a hundred times.

6>. Parameterized management

For different security inspection levels or different use occasions, there should be built-in security inspection levels issued by international authoritative organizations, which can provide users with multiple sets of parameters according to different security inspection level requirements, so that they can be directly selected when using. At present, most walk through metal detectors can provide this quick selection of parameters or remote parameter changes, or formulate and store completely personalized parameter solutions. Some walk through metal detectors support smart card authorization operations.

7>. Qualification and security certification

The production of walk through metal detectors must pass the quality security inspection certificate with inspection qualifications (according to the inspection performance requirements and inspection methods of GB15210-2003, all test items including environmental adaptability are inspected), and the export must pass the CE certification. The smaller electromagnetic field will not harm pregnant women, life support systems and multimedia disks.